For 58 cases of canine mast cell tumors, we measured the tumor volume reduction following one to four weeks of treatment with prednisolone administered once per day. The median dose of prednisolone was 21.5 mg/m
2. We observed tumor reduction in 35 cases, with a response rate of 60.4%. In addition, the median times for obtaining a complete or partial response were 14 and 10.5 days, respectively. Among the response group of 35 cases (complete response = 7, partial response=28) and the non-response group of 23 cases (no change [stable disease] = 18, additional swelling [progressive disease] =5), we observed a significant difference in the initial tumor volume (
P < 0.001), with the median volume being 2.69 cm
3 for the response group and 18.85 cm
3 for the non-response group. We have therefore reconfirmed the importance of using prednisolone as a treatment for canine mast cell tumors and we have clearly shown that the smaller the tumor volume, the more effective the prednisolone treatment will be.
View full abstract